There's a plan for readers to get points for participation, and those readers with a higher score will get more privileges. They might be offered access to special content and at some point in the future they might get real-world rewards.
Readers can also invite their friends, share notes, and discuss the ebooks they're reading. It’s also possible just to read the book and ignore all the community aspects of the site, so even digital hermits are welcome.
In exchange for offering the free content, publishers will get analytical reports of how readers interact with their titles, including time spent, pages read, and where readers stopped.
I'm hoping that publishers don't decide to misuse the data they get. It would be all too easy to decide to shift an ending or rewrite a book based on this, and that would be bad.
let me give you an example. The movie Edward Scissorhands reportedly tested poorly when it was first shown to test audiences. A lot of viewers didn't get the characters, motivation, or who was supposed to be the villain. Had the movie been rewritten based on the test audience it would have ruined what is now a classic of the genre.